Lock



M. FALK May 7, 1935.

LOCK

Original Filed April 23, 1930 drawings inwhich Patented May 7, 1935 e UN LSTATE PAT This invention relates to a tumbler lock of the type in which the plugcan be removed as a whole and replaced in a simple and convenient manner. r

The principal object of this invention is to provide an arrangement whereby-the key for use in removing the plug 'canbe blank to provide means. for preventing the turning of the plug" when the blank key is in the plug, and to provide means for locking the blank key in the'plug so that the key cannot be removed without the plug, said means being easily manipulated when the plug is withdrawn. I

Other objects and advantages of the invention will appear hereinafter.

Reference'is to, be had to the accompanying Fig. 1 is a sectionalview of the parts of the lock except the plug, which is shown in elevation and in unlocked position; I V Figs. 2 and 3 are transverse sectional views on the lines 22 and 3-3 respectivelyof Fig. 1; Fig. 4 is a sectional view of theplug and associated parts with the ordinary key in positionand showing the plug unlocked so that it can be turned;

Fig. 5 is a similar view showing the blank key in position, the plugjbeing in the same position asfiin Fig. 4 and released so that it can be pulled ou Fig 6 is a sectional viewron the line 6-45 of Fig. 5,-and

Fig. 7 is a viewlike locked position.

It is now well known that it a-yveryiconvenientthing to be able'to remove theplug of a tumbler lock and replace it. Certain devices have beenfsuggestedfo'r this purpose. In accordance with this invention 1 provide a spring for en'tering a-circumferential groove and holding the plug in its longitudinal positionanda mov able element in the plug, which can be operated by a blank key, but not by the locking key, for displacing the springandallowing the plug to be I have shown the invention as applied to a lock having a cylindrical casing I0 and a' plug 1 l with an end 12 thereon havingan eccentriostud l3- for'diifaltihg'th' lock. The plug also has an annular groove 14 around it into which extends a shoulder on a spring l5. This. spring is so shaped as to be movable on the cylinder and has this shoulder projecting through an opening in the cylinder into the groove [4. Inthis position obviously, as shown in Fig. 4, it prevents the is forced out.

removal of. the plug.- The plugfhas a rounded or slanting circular surface 23 for forcing the spring into place when the; plug is inserted 1' The ordinarylockihg key I 6 shown'in Fig. 4 operates the lock inlthe usual Way and can have no effect on thespring IB The plug is provided with a longitudinal recess ll' in which operates aslide l8 pressed toward the key by a spring l9 and vhaving a round ended lor cam projection .tii which is flush With the cylindrical outside surface of the plug. By pushing. the slide in v against the spring [9 this projectionmwill entershowninFig; 5. ,fIt will be obvious that whe'ni' in the positiont shown in Fig. 5,; the shoulder jon'1 ,tl1e spring l5 isentireIy'pushedback outiof' the groove so that there is no'jopposition to there'moval of 'the plug. This is accomplished by providing a special key 2! having apblank shapeand longer than the key lfi. Itsendiengages theendof the slide l8. when the key ,2I5is inserted at the time when the plugis in unlocking position andf'o'rces'thisslide into the groove M, as describediabove, whereupon without turning'the plug thejspring Now the key and plug maybe withdrawn because the spring 15 is'in unlocking position andthe plug can be re-inserted with the ordinary key It because the means for,holding the plug in position is the spring member [5 which'will" slide up the incline aroundits sur face 23 into the groove I4 without the use of the Fig. 5 with the partsin key 2|.

The key 2! canbe made in the form ofa blank because it does not have to be turnedin the lock and in fact cannot be turned in that case. Some of the tumblers 22.will be left sticking out into the usual ,slots provided in the interior, of the at that time. .The'. tumbler 22 at the end enters a'notch 25in the key 21 so thattlie key cannot I betaken out Withoutfthe plug." This. tumbler can be depressed by hand. after the plug is removed, in orderftofreethe key from it. e V No small pieces'are used that might get lostand the special key is all in one piece and. is" made as ablank-without bitting'. The special key if the'slide 20 were made without an extension 34' could bems'erted'm the'plug, with the plug in locking or unlocking position, two positions diametrically opposite, and theplug could not be then turned by the special key. I I

'I'hisconstruction, as so far described, permits the groove Ill and push thespring 15 back, as we a cylinder. Therefore the plug cannot emmed the blank key to be inserted in either the locked were made without the end orextension 34. However, in case the key 2| could be inserted all the way when the look was locked, thekey would be held therein by the end tumbler 22 and, as this key cannot be turned, the lock would be stuck and could not be unlocked or the key removed. To avoid this difiiculty I provide a perforation 32 in the locking bolt 33 and extend the slide l8 by providing an end 34 thereon. The end 34 and perforation SZ-register when the plug is in unlocked position so that the key can be inserted fully, the slide 20 moved far enoughto cam out the spring l5 and the plug can be re:-

moved. But, when in locked position the end 34 engages 'a solid part of the bolt 33 and the cam 20 cannot be moved far enough to cam spring I5 to plug releasing position. I

Although I have illustrated and described only one form of the invention I am aware of the fact that modifications can be made therein by any person skilled in the art Without departing yielding means back; said movable member being so located that .thelocking key will not move it into the groove but that it can be so moved to free the plug by introducing'a long key in the key slot which will project beyond the position at the extreme end of the locking key when the plug is in unlocked position.

2. In a cylinder lock, the combination with the cylinder and plug, the plug havingan'iannular groove tlierearoundfof'means adapted to enter said groovefrom the cylinderto hold the plug in after it has once been assembled, a movable member carried by the plug and adapted to be moved into said groove to push said means back as it is pushedin and permit the plug to'be removed, said plug being removed by a blank key; long enough to push said movable member into said groove, and having a shoulder adapted to receive the last tumbler of the plug behind it,

when the blank key is pushed all the way in, to

insure that the plug will beremoved when, the blank key is pulled out.

' 3. In a cylinder lock, the combination of a,

cylinder or casing and a removable plug, the cas ing having a slot through its wall and plug,holding means on the casing having a shoulder projecting inwardly through the slot, the plug having an annular groove for receiving said shoulder and having a movable member with a projection normally located out of the groove but capable of being forced backwardly into the groove to pushthe shoulder entirelyout of the groove, said lock being operable by a locking key adaptedto'operate the look without aifecting the position of. said movable member and bya special key formedof blank shape and extended enough so that when inserted in unlocking position, said extension will push said slide into said groove and release the plug.

4. In a cylinder lock, the combination of a cylinder or casing and a removable plug, the casing having a slot through its wall and a spring on the casing having a shoulder projecting inwardly through the slot and the plug having an annular groove for receiving said shoulder to hold the plug in place when it has been introduced, said plug also having a spring pressed slide therein with a projection normally held back by its spring out of the groove but capable of being forced backwardly into the groove to push the shoulder of the spring entirely out of the groove, said lock being operable by a locking key without affecting the position of said slide and by a special key formed of blank shape and extended enough so that when inserted in unlocking position, said extension will push said slide into said groove and release the plug.

5. In a lock, the combination with a cylinder, a plug, and a bolt connected with the plug to be operated thereby, said bolt having an opening therein, of yielding means adapted to enter the plug to holdit in after it has once been assembled, a movable member adapted to push the yielding means'back andpermit the plug to be removed, whereby a special key having a projecting end will enter the opening in the bolt so that the key can be moved in to the full extent when the bolt is in one position, said bolt constituting means for preventing the special key from being moved in when thebolt is in another position.

6. In a cylinder lock, the combination with a cylinder and plug, and a bolt connected with the plug to be operated thereby, said bolt having an opening therein, the plug having an annular groove, of yielding means adapted to enter the plug to hold the plug in after ithas once been assembled, a movable member carried by the plug and adapted to move into said groove to pushv the yielding means back and permit the plug to be removed; whereby a special keyhaving a pro jecting end will enter the opening so that the key can be moved in to the full extent when the bolt is in one position, said. bolt constituting means for preventing the special key from being moved. in when the bolt is in another position.

7 7. In a lock, the combination with a cylinder, a plug and a locking bolt connected with the plug to be operated thereby, the plug having an an. nular groove and the bolt having a perforation, of yielding means adapted to enter the groove to hold the plug in after it has been assembled, a slide carried by the plug and adapted to be moved into the groove to push said yieldingmeans back,

said movable member being so located that the locking key will not move it butthat it can be moved to free-the plug by the introductionof a long key in the key slot, said slide having an end in position to enter the openingin the bolt when the plug is in unlocked position and the long key is inserted to push the slide in, whereby when the plug is in locked position the bolt will serve as a stop to prevent the slide, and therefore the long key, from being pushed in to the extreme position.

MORRIS FALK. 

